• Title/Summary/Keyword: Cuboid

Search Result 64, Processing Time 0.026 seconds

Assessment of the Location of the Peroneus Longus Tendon in the Cuboid Groove Using 3D Isotropic Fast Spin-Echo MRI

  • Lee, Ji Yoon;Choo, Hye Jung;Lee, Sun Joo;Jung, Joon-Yong;Kim, Dong Wook;Baek, Jin Wook;Heo, Young Jin;Gwak, Heui-Chul
    • Investigative Magnetic Resonance Imaging
    • /
    • v.24 no.1
    • /
    • pp.21-29
    • /
    • 2020
  • Purpose: To investigate normal location of the peroneus longus tendon (PL) in the cuboid groove by evaluating it between ankles with no significant abnormality (asymptomatic group) and those with retromalleolar PL dislocation (dislocation group) using three-dimensional isotropic fast spin-echo (3D-FSE) magnetic resonance imaging (MRI) of the ankle. Materials and Methods: Thirty-six and 32 3D-FSE ankle MRI were assigned to the asymptomatic group and the dislocation group, respectively. Using multiplanar reformatted 3D-FSE, qualitative PL location (i.e., outside, overlying, and inside in relation to the cuboid groove), quantitative PL location (i.e., distance between the proximal margins of PL and cuboid groove), and cuboid groove size were measured in lateral, middle, and medial levels of the cuboid groove. Results: In the asymptomatic group, 64%, 42%, and 11%, respectively, had the outside or overlying-located PL in lateral, middle, and medial levels of the cuboid groove and the quantitative location gradually decreased from lateral to medial level. Qualitative and quantitative PL locations were not significantly different between the asymptomatic group and dislocation group. Cuboid groove size showed significant negative correlation with quantitative PL location in both groups. Conclusion: Outside- or overlying-located PL in lateral and middle levels of the cuboid groove would be a normal finding, regardless of PL status at the retromalleolar level.

LAMINAR FLOW OVER A CUBOID (직육면체를 지나는 층류 유동)

  • Kim, Dong-Joo
    • Journal of computational fluids engineering
    • /
    • v.13 no.1
    • /
    • pp.57-62
    • /
    • 2008
  • Laminar flows over a cube and a cuboid (cube extended in the streamwise direction) are numerically investigated for the Reynolds numbers between 50 and 350. First, vortical structures behind a cube and lift characteristics are scrutinized in order to understand the variation in vortex shedding characteristics with respect to the Reynolds number. As the Reynolds number increases, the flow over a cube experiences the steady planar-symmetric, unsteady planar-symmetric, and unsteady asymmetric flows. Similar to the sphere wake, the planar-symmetric flow over a cube can be divided into two different regimes: single-frequency regime and multiple-frequency regime. The former has a single frequency due to regular shedding of vortices with the same strength in time, while the latter has multiple frequency components due to temporal variation in the strength of shed vortices. Second, the effect of the length-to-height ratio of the cuboid on the flow characteristics is investigated for the Reynolds number of 270, at which planar-symmetric vortex shedding takes place behind a cube. With the ratio smaller than one, the flow over the cuboid becomes unsteady asymmetric flow, whereas it becomes steady flow for the ratios greater than one. With increasing the ratio, the drag coefficient first decreases and then increases. This feature is related to the flow reattachment on the side faces of the cuboid.

Iceberg Query Evaluation Technical Using a Cuboid Prefix Tree (큐보이드 전위트리를 이용한 빙산질의 처리)

  • Han, Sang-Gil;Yang, Woo-Sock;Lee, Won-Suk
    • Journal of KIISE:Databases
    • /
    • v.36 no.3
    • /
    • pp.226-234
    • /
    • 2009
  • A data stream is a massive unbounded sequence of data elements continuously generated at a rapid rate. Due to the characteristics of a data stream, it is impossible to save all the data elements of a data stream. Therefore it is necessary to define a new synopsis structure to store the summary information of a data stream. For this purpose, this paper proposes a cuboid prefix tree that can be effectively employed in evaluating an iceberg query over data streams. A cuboid prefix tree only stores those itemsets that consist of grouping attributes used in GROUP BY query. In addition, a cuboid prefix tree can compute multiple iceberg queries simultaneously by sharing their common sub-expressions. A cuboid prefix tree evaluates an iceberg query over an infinitely generated data stream while efficiently reducing memory usage and processing time, which is verified by a series of experiments.

Basidiospore Development and Fine Structure in Rhodophyllus muraii var. albus (흰꼭지외대버섯의 담자포자의 발생과 미세구조)

  • Cho, Duck-Hyun
    • Korean Journal of Plant Resources
    • /
    • v.6 no.2
    • /
    • pp.165-170
    • /
    • 1993
  • Apexes of basidia in Rhodophyllus muraii var. albus are divided into four sections or depressed in the center. A spore is formed by inflation of the apex of the sterigma. The apex of the sterigma is swollen and changed from a papilla through a peinsform and a club into a globeform. Six spots of globose spore are regularly or irregularly depressed with hilum axes. Finally the spores come cuboid.

  • PDF

Basidiospore Development and Fine Structure of Entoloma (외대버섯속의 담자포자의 발생과 미세구조)

  • Cho, Duck-Hyun
    • Korean Journal of Plant Resources
    • /
    • v.6 no.2
    • /
    • pp.141-145
    • /
    • 1993
  • Apexes of basidia in Rhodophyllus(synonyum of Entoloma) muraii var. albus are divided into four sections or depressed in the center. A spore is formed by inflation of the apex of the sterigma. The apex of the sterigma is swollen and changed from a papilla through a penisform and a club into a globeform. Six spots of globose spore are regularly or irregularly depressed with hilum axes. Finally the spores are cuboid. Basidia of Entoloma squamiferrum are developed from hymenium layer of crator-shaped parabasidium. Apex of basidium is flat or depressed in the center. Although four sterigmata are developed, only two sterigmata are symmetrically swollen to two spores in certain basidia. It means that two sterigmata among four sterigmata are infertile. The apex of the sterigma is swollen into a paillaform, and then turned into a penisform. It is swollen from a clubform into a globeform. Six spots of the surfaces of globose spore are deperssed with hilum axes. Finally the spore is cuboid, and then it is released from hilum. Four sterigmata of papillaform of E. violaceobrunneum are developed from cartor-shaped basidium. The apex of sterigma is swollen to a small globeform. And then it is swollen to a clubform. The clubform is again swollen to a ellipticalform, and then more than six spots of spore surfaces are ramomly depressed with hium axes. When the depression of surface of a elliptical spore is over, it is the multi-angular spore of the heterometrical-form.

  • PDF

Constructing AR Game Space through Cuboid Detection in Indoor Environment (실내 환경에서 직육면체 검출을 통한 AR 게임 공간 구성)

  • Kim, Ki-Sik;Park, Jong-Seung
    • Journal of Korea Game Society
    • /
    • v.21 no.5
    • /
    • pp.3-16
    • /
    • 2021
  • In this paper, we propose a method of constructing AR game spaces through cuboid detection in indoor environment. Conventional spatial recognition methods can detect planes only in limited spaces that can be well observed. They are also vulnerable in density and noise. The proposed method overcomes the limitations of the conventional method by constructing AR game spaces by a method of detecting OBBs from spherical videos. Experimental results showed that the proposed method is faster than the conventional method and it is also robust against environmental constraints such as changes in density and noisy.

An Efficient Incremental Maintenance Method for Data Cubes in Data Warehouses (데이타 웨어하우스에서 데이타 큐브를 위한 효율적인 점진적 관리 기법)

  • Lee, Ki-Yong;Park, Chang-Sup;Kim, Myoung-Ho
    • Journal of KIISE:Databases
    • /
    • v.33 no.2
    • /
    • pp.175-187
    • /
    • 2006
  • The data cube is an aggregation operator that computes group-bys for all possible combination of dimension attributes. %on the number of the dimension attributes is n, a data cube computes $2^n$ group-bys. Each group-by in a data cube is called a cuboid. Data cubes are often precomputed and stored as materialized views in data warehouses. These data cubes need to be updated when source relation change. The incremental maintenance of a data cube is to compute and propagate only its changes. To compute the change of a data cube of $2^n$ cuboids, previous works compute a delta cube that has the same number of cuboids as the original data cube. Thus, as the number of dimension attributes increases, the cost of computing a delta cube increases significantly. Each cuboid in a delta cube is called a delta cuboid. In this paper. we propose an incremental cube maintenance method that can maintain a data cube by using only $_nC_{{\lceil}n/2{\rceil}}$ delta cuboids. As a result, the cost of computing a delta cube is substantially reduced. Through various experiments, we show the performance advantages of our method over previous methods.

Design of an Inference Control Process in OLAP Data Cubes (OLAP 데이터 큐브에서의 추론통제 프로세스 설계)

  • Lee, Duck-Sung;Choi, In-Soo
    • Journal of the Korea Society of Computer and Information
    • /
    • v.14 no.5
    • /
    • pp.183-193
    • /
    • 2009
  • Both On-Line Analytical Processing (OLAF) data cubes and Statistical Databases (SDBs) deal with multidimensional data sets. and both are concerned with statistical summarizations over the dimensions of the data sets. However, there is a distinction between the two that can be made. While SDBs are usually derived from other base data, OLAF data cubes often represent directly the base data. In other word, the base data of SDBs are the macro-data, whereas the core cubiod data in OLAF data cubes are the micro-data. The base table in OLAF is used to populate the data cube with values of the measure attribute, and each record in the base tables is used to populate a cell of the core cuboid. The fact that OLAF data cubes mostly represent the micro-data may make some records be absent in the base table. Some cells of the core cuboid remain empty, if corresponding records are absent in the base table. Wang and others proposed a method for securing OLAF data cubes against privacy breaches. They assert that the proposed method does not depend on specific types of aggregation functions. In this paper, however, it is found that their assertion on aggregate functions is wrong whenever any cell of the core cuboid remains empty. The objective of this study is to design an inference control process in OLAF data cubes which rectifying Wang's error.

The Effect of Mathematics Classes Using AlgeoMath on Mathematical Problem-Solving Ability and Mathematical Attitude: Focusing on the 'Cuboid' Unit of the Fifth Grade in Elementary School (알지오매스 기반 수업이 수학적 문제해결력 및 태도에 미치는 효과: 초등학교 5학년 '직육면체' 단원을 중심으로)

  • Seung Dong Lee;Jong Hak Lee
    • Journal of Science Education
    • /
    • v.48 no.1
    • /
    • pp.47-62
    • /
    • 2024
  • The purpose of this study is to investigate the effects of classes using AlgeoMath on fifth grade elementary students' mathematical problem-solving skills and mathematical attitudes. For this purpose, the 'cuboid' section of the 5th grade elementary textbook based on AlgeoMath was reorganized. A total of 8 experimental classes were conducted using this teaching and learning material. And the quantitative data collected before and after the experimental lesson were statistically analyzed. In addition, by presenting instances of experimental lessons using AlgeoMath, we investigated the effectiveness and reality of classes using engineering in terms of mathematical problem-solving ability and attitude. The results of this study are as follows. First, in the mathematical problem-solving ability test, there was a significant difference between the experimental group and the comparison group at the significance level. In other words, lessons using AlgeoMath were found to be effective in increasing mathematical problem-solving skills. Second, in the mathematical attitude test, there was no significant difference between the experimental group and the comparison group at the significance level. However, the average score of the experimental group was found to be higher than that of the comparison group for all sub-elements of mathematical attitude.

A Study on Graphic Program for 3D Image Display System (실시간3차원 그래픽 프로그램 개발에 관한 연구)

  • 배성찬;권승탁;양연식
    • Proceedings of the IEEK Conference
    • /
    • 2001.06d
    • /
    • pp.227-230
    • /
    • 2001
  • In this paper, We present a 3D image data for ocular refina. This 3D display techniques are used voxel(cuboid) projection. Voxel is 3D reconstruction method of the pixel. In this paper, 3D image display system is constructed under PC environment and programed based on modular programming by using Visual C++. The hole procedures are composed of data preparation, 3D Display over transformation and scaling.

  • PDF